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View Full Version here: : 3D printed counterweight, excellent idea!


bojan
11-08-2017, 09:32 AM
While searching thingiverse for ideas for something else, I found this design (https://www.thingiverse.com/thing:2441978).
I have already made couple of large concrete counterweights in the past (using plastic pots and boxes as cast/enclosure and plastic pipes/tubing for central hole), and I found this idea an excellent alternative, since it widens the choice of shapes and sizes for counterweight.

JA
11-08-2017, 09:59 AM
Hi Bojan,

That's a great use for 3D. You could even go for steel fillings or lead shot inside, to really increase the mass many times over sand/dirt/cement.

Best
JA

Wavytone
14-08-2017, 02:26 PM
Another idea I've had for a while is that counterweights for EQ mounts should really be made in pairs with the central hole decidedly off-axis.

The off-axis weights could then be used to balance OTA's that have a centre of gravity offset from the centre of the dovetail, e.g. a heavy finder, or the current trend for monster eyepieces in 2" diagonals on the back of small refractors.

2 are needed so you can also find an arrangement that is neutrally balanced.

JA
14-08-2017, 07:49 PM
Hi WT,
You could also create the same eccentricity by distributing the mass / filler inside Bojan's central hole 3D printed counterweight shells. Fill half or whatever proportion you need with lead shot and or steel filings with resin or silicone to hold it in place and the other half with cement/sand or empty. And then it all still LOOKS normal, just turn the counterweight to adjust the distribution of mass as you've already explained. You probably should just then mark them as the eccentric masses, with the position of centre of mass on their sides, so that they can be seen when mounted. Also that way no new 3D program is required.

Best
JA